Compressor



D. PICA COMPRESSOR Jan. 8, 1952 2 SHEETSSHEET 1 Filed Sept. 17. 1949 FIG. I

FIG.2

5 m a B 2 5 M C A m W 7 2 m 7 IL I09 E N M. I A D H N a D. PICA COMPRESSOR Jan. 8, 1952 2 SHEETS-SHEET 2 Filed Sept. 17. 1949 FIG. 4

FIG. 3

INVENTOR: DANIEL PICA ATT'YS 3 Claims.

This. invention relates to pump-operating mechanism and particularly to a form of electricallycdriven compressor of extremely simple and compact construction for use in places where the saving of space is of great importance such, for-example, as the machine-housing compartments of. refrigerators.

The main objects of this invention are to providexair improved form of gas compressing and pumping mechanism; to provide an improved mechanism of this kind that comprises a minimum of parts in space-saving arrangement; and toprovide an improved form of pump in which the piston rotates and reciprocates simultaneously and Whichis of such construction that the piston performs both the compressing function and the valving function.

g: An illustrative embodiment of this invention is shown in the accompanying drawings in which:

Figure 1 is an axial section of an electromotor compressor embodying the present invention, showing the parts in positions corresponding to the upper end of the compression stroke of the pump piston.

Fig. 2 is a similar view showing the parts in the relative positions they occupy at the time when the pump piston has reached the mid-position of its downward or suction stroke.

Fig. 3 is a similar view showing the parts in positions corresponding to the end of the downward stroke of the piston.

Fig. 4 shOWs the parts in the positions occupied when the piston is midway in its upward stroke.

Fig, 5 is a sectional detail taken on the line 5-5 of Fig. 2.

Fig. 6 is a sectional detail taken on the line 6-6 of Fig. 2.

Fig. 7 is a fragmentary perspective view, partly broken away, of the pump cylinder block illustrating the arrangement of ports therein for control by the rotation and the reciprocation of the piston.

Fig. 8 is a schematic diagram of the relation of the ports in the piston and cylinder walls.

In the form shown in the drawings the motor comprises 'a stator I and rotor 2, illustrated somewhat diagrammatically, and arranged for rotation of the rotor about the vertical axis. The rotor core is fast on a tubular driving shaft 3 journaled in a foot-step bearing don a horizontal partition 5 of the frame 6 and upper bearing I mounted on a horizontal partition 8 in the frame 6.

A driven shaft 9 extends telescopingly into the driving shaft 3 to which it is splined at IU so as uN lrso STATES PATENT OFFICE COMPRESSOR Daniel Pica, Chicago, Ill., assignor of one-half to Frank Kemptner, Silver Lake, Wis.

Application September 17, 1949, Serial No. 116,270

to be free to move axially with respect to the driving shaft 3 but compelled to rotate with said shaft 3. The driven shaft 9 is rigidly fixed to or integral with the pump piston II on the upper end of the shaft, which piston is shaped to fit within and move relative to the pump cylinder body l2 which is carried at the upper end of the frame 6.

The cylinder head 13, in the form shown, has a plunger-like body I4 of frusto-conical form tapering convergently away from the cylinder head and which extends into a correspondingly shaped chamber portion I5 which together with clearance space I6 above the piston forms the pump chamber I5, I6 of the cylinder, thus greatly reducing the length .of the cylinder body I2 with respect to the pistons stroke. The tapered walls of the chamber cavity I5 in the piston II and of the plunger I4 are so related as to provide unobstructed communication between the chamber spaces I5 and I6in the cylinder and piston respectively, with a minimum of clearance at the end of the compression stroke, j

Located at a point intermediate of the bearing 1 and the cylinder body I2 there is a yoke journal 11 which is fixed on the driven shaft 9 by a cotter pin I8. The yoke journal I! has the axis of its bearing surface disposed at an angle to the axis of the driven shaft 9 and has a yoke I9 journaled thereon preferably by means of a ball bearing 20. The yoke I9 is appropriately secured against axial displacement on the bearing surface of the journal I l and has an arm 2| extending radially from one of its sides and comprising a journal portion which is slidably and rotatably seated in a bearing ring 22 which in turn is journaled in the frame 6 for limited tilting about an axis at right angles to the plane that is defined by the axis of the driven shaft 9 and the yoke arm journal 2|.

When the shaft 9 is rotated, the yoke I9, through its connection with the frame at 22 is held against rotation with shaft 9 and through its inclined yoke journal I! on the shaft 9 is caused to tilt or wobble about the shaft 9 between the various positions in which it is shown in Figs. 1 .to 4 of the drawings. Thus the driven shaft 9 is compelled by the yoke I 9 to reciprocate axially as it rotates, there being one complete up-and-down stroke for each full rotation of shaft 9 on which. the pump piston II is fixed.

The pumping chamber portion I5 has a port 23 directed radially outward through the wall of the hollow piston toward the cylinder wall where, through the movements of the piston, it is brought alternately into communication with an inlet port 24 and an outlet port 25 in the cylin der wall. These ports are extended in the form of spiral grooves 26 and 27 in the cylinder walls, and these grooves are shaped and positioned to register with the piston port 23 in such manner that the port 23 registers. with the inlet port 24 during the major portion of the suction stroke of the piston and with the outlet port 25 during part of the compression stroke. The port 23, as will be understood, is out of registry with either the ports 24 or 25 at the extreme ends of the piston stroke.

The degree of compression is determined by the length of the groove 21. If it were to be made of such length and form as to register with the port 23 during the entire exhaust stroke of the piston, there would be no compression and only displacement of fluid as in a pump for liquid. On the other hand, if the exhaust port is open only durin a fractional portion of its movement at the end of the compression stroke, the compression will be inversely proportional to this fraction as compared with the full stroke.

Although but one specific embodiment of this invention is herein shown and described, it will he understood that numerous details of the struc ture shown may be altered or omitted without departing from the spirit of the invention as defined by the following claims.

I claim:

1. A compressor, comprising a cylinder, a piston therein, driving mechanism operatively connected to said piston for rotating and simultaneously reciprocating said piston axially within said cylinder, a head on one end of said cylinder, a plunger on said head, said piston having a chamber formed therein to receive and coact with said plunger for compressing a gaseous medium, a port in said piston leading transversely outward from said chamber adjacent the end of said chamber that is distant from said cylinder head, an outlet port in said cylinder positioned to register with said piston port when said piston is 4 near the end of its compression stroke, and an inlet port in said cylinder positioned to register with said piston port during the suction stroke of said piston.

2. A compressor as specified in claim 1, wherein the plunger on the cylinder head is tapered oonvergently away from said head and the chamber in the piston is correspondingly tapered for minimum clearance at the end of the piston stroke toward said head.

3. A compressor, comprising a cylinder, a piston therein, driving mechanism operatively connected to said piston for rotating and simultaneously reciprocating said piston axially within said cylinder, a head on one end of said cylinder, a plunger on said head, said piston having a chamber formed therein to receive and coactwith said plunger ior compressing a gaseous medium, a port in said piston leading transversely outward from said chamber adjacent the end of said chamber that is distant from said cylinder head, an outlet port in said cylinder positioned'to register with said piston port during a relatively small portion of the movement of said piston near the end of its compression stroke, and an inlet port in said cylinder positioned to register with said piston port durin the major part of the suctionstroke of said piston. V

DANIEL PICA.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 378,847 Nash Feb. 28, was 1,799,167 Hulsebos Apr. 7, 1931 FOREIGN PATENTS Number Country Date 215,257 Great Britain May 8, 1.924 542,213 France Aug. 8, 1922 

